Flower-like patterns on the surfaces of many sea stars are anything but 'bee-friendly'. A pretty little arrangement surounding the spine of a giant sunflower star is, in fact, a cluster of two-jawed pincer claws that act like miniature vise grips to protect the sea star from predators or microscopic larvae of other animals. These jawed structures are called pedicellaria. The sunflower star, Pycnapodia helianthoides, has two sizes of pedicellaria, but it is not known how the two provide different roles.

The balloon-like structures surrounding the purple cluster are the skin-gills (papulae) that exchange gases and waste products with the environment. Each papula is a sac that protrudes out through holes in the skeleton. Its contents are thus connected to the body cavity of the sea star. Researchers have discovered that sea stars can actually take dissolved organic nutrients out of sea water under some circumstances, and so they can gain some of their nutrition by slurping in molecules from the very dilute organnic soup in which they live.